Benjamin t



(No Model.)

B. T. 'BABBITT. BALANGED ROTARY VALVE.-

Patented Jan. 2;, 1883.

V UNITED STATES.

PAT NT. OFFI E.

BENJAMIN '1. BABBITT, or New YORK, N. .Y.

BALANCED ROTARY VALVE.

SPECIFICATION forming part of Letters Patent No. 269,992, dated January2, 1883. Application filed October 28. 1882. (No model.)

To all whom it may concern:

Be it known that I, BENJAMIN T. BABBITT, a citizen of the United States,residing in the city, county, and State of New York, have invented newand useful Improvements in Balanced Rotary Valves for Steam-Engines, ofwhich the following is a specification.

My invention relates to improvements in balanced valves forsteam-engines, and it particularly relates to that class of valvescommonly known as oscillating valves, for effectingthe induction andeduction of steam to and from the cylinder.

The object of my invention is to balance such valves 'by causing thesteam from. the boiler to exert its pressure on the under side of orface of the valve, to counteract thepressare exerted by the steamentering the valve,

valve-chest, or casing by the induction-pipe.

My invention consists in the combination, with an oscillatingsteam-valve having an inlet-passage, a port or ports, and a bridge, of avalve casing or shell formed with longitudinal passages leading from thesteam-inlet, balancing-cavities arranged on each side of the portorports in the valve and on the under side of the valve, or on theopposite side thereof to the steam-inlet, and annular passages extendingfrom the longitudinal passages to the said cavities, all in such mannerthat steam is conveyed from the inlet to the passages and cavities forbalancing the valve, as will be more fully hereinafter explained.

In most cases I prefer to employ a balancing-cavity on each side of theports, with corresponding passages leading from the inlet. The balancingcavity or cavities should be of an area equal, or nearly so, to the areaof the surface of the valve exposed to the action of the incoming steam.

The accompanying drawings formpart of this specification, andillustratev what I consider the best means of carrying out my invention.I

Figure 1 is a central vertical section of a valve case or cylinder andvalve with my improvements applied theretoand adapted to admit andexhaust steam alternately to both ends of the cylinder. Fig. 2 isacross-section on the linea'win Fig. 1. Fig. 3 is a correspondingcross-section 0n theline 3 y of Fig. 1. Fig. 4 shows a cross-section ofa valve case or 1 cylinder and valve with my improvements appliedthereto and adapted for the admission and exhaust of steam from one endof the cylinder.

In each of the views similar letters of reference are employed toindicate corresponding parts wherever they occur.

A represents the valve chest or casing, and B the valve. The valve B maybe of'cylindrical form, as shown in Figs. 2 and 3, or conical, and isprovided with spindles or journals 1) bthe one received into a bearingin one end of the valve chest or casing, while the other works in andthrough a suitable stuffingbox, B in the other end. A is the inlet forsteam from the boiler, by means of which the steam is conducted to theinlet-passage (3, which is provided with a passage formed centrallythrough the valve, and which is large enough at its upper mouth or endto allow of free access of steam thereto from the inlet-pas: sage at alltimes, irrespective of position of the valve B. At its lower end thepassage 0, according to the arrangement shown by Figs. 1, 2, and 3, isdivided into two ports, 0 0, by

the interposition of the curved portion or bridge 01, forming theexhaust-cove D'.

E E are ports formed in the valve chest or casing, and leading to theopposite ends of the en gine-cylinder, for the induction and eduction ofsteam thereinto, and each of which in the operation of the valve isalternately brought into communication with its respective port 0 or c,for the admission of steam to one end or otherof the steam-cylinder, orwith the cove D, for the purpose of exhausting the steam, which is thenled away by the exhaust-port F and exhaust-passage F, as is wellunderstood.

G G are small passages or channels, formed in the upper side of theinterior of the case or cylinder A, on each side of the main ports,forthe purpose of conducting steam from theinletpassage A to circularpassages G G, formed around the inner periphery of the case or cyl inderA, and which terminate in both directions in a balancing-cavity, H,formed in the casing Aon the under side of the valve B, or on theopposite side to that at which the pressure of the inlet-steam isexerted, and on the same side as the ports 0 c and cove D. The

cavities H are of an aggregate area approximately equal to the area ofthe surface-bridge d, and such other portions of the valve A as areexposed to the action of the inlet-steam,in order that the valve may beapproximately balanced.

In Fig. 4 I have shown the valve B provided with only a single port, 0,adapted to be alternately closed by the cylinder A or open to thecylinder-port E. The exhaust-port F-and exhaust-passage are arranged onone side of the center of the valve and cylinder, while thecylinder-port is on the other side.

Having thus described my invention, what I claim, and desire to secureby Letters Patent, 1s-

The combination, With an oscillating steamvalve having the passage 0,port or ports 0 c, exhaust D, and bridge d, of the valve casing or shellA, formed with longitudinal passages G G, leading from the inletA,balancing-cavities H H, arranged on-each side of the valve port or portsand on the under side of the valve, or on the opposite side thereof tothe inlet, and annular passages G G, extending from the longitudinalpassages to the said cavities, substantially as and for the purposedescribed.

, "B. T. BABBITT.

Witnesses:

FREDK. HAYNES, O. E. SUNDGREN.

